Key findings
- 1Hydrogenation (adding hydrogen to liquid oil) was margarine's original method; it created trans fats now banned by the FDA
- 2Interesterification (rearranging fatty acids with enzymes or catalysts) replaced hydrogenation but is equally industrial
- 3Margarine naturally looks gray-white; beta-carotene is added to achieve the yellow color consumers associate with butter
Why is Margarine Level 3 on average?
Margarine's history is a case study in industrial food processing. Originally patented in 1869 as a butter substitute, early margarine used beef tallow. The 20th century shifted to vegetable oils, but liquid oils needed to be solidified. Partial hydrogenation (bubbling hydrogen gas through oil with a nickel catalyst at high temperature) was the original method, but it created trans fats, and the FDA has since banned partially hydrogenated oils from the food supply. Most modern margarines use interesterification instead: enzymes or chemical catalysts rearrange the fatty acid positions on glycerol molecules to change the oil's melting point. While this avoids trans fats, it is still a laboratory-scale chemical modification. Additional ingredients include emulsifiers (soy lecithin, mono/diglycerides), colorants (beta-carotene to mimic butter's yellow), artificial butter flavoring, and preservatives (EDTA, potassium sorbate). In our analysis, margarine averages a Processing Score of 7.2, which is Level 3.
How 146 margarine products break down
Share of products at each processing level, in our analysis.
Margarine brand comparison
From least to most processed in our database.
How to read a margarine label
- 1
"Hydrogenated" or "partially hydrogenated" oils indicate the older trans fat process, avoid these
- 2
Modern margarines use "interesterified" oils or palm oil blends but is still industrial but trans fat-free
- 3
Beta-carotene is added for yellow coloring; margarine is naturally gray-white
- 4
Real butter is two ingredients (cream and salt), against a much longer list for margarine
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Frequently asked questions
Is margarine healthier than butter?
The health debate is separate from processing. From a processing standpoint, butter is two ingredients (cream and salt) while margarine is chemically modified vegetable oils plus emulsifiers, colorants and preservatives. In our analysis, margarine averages a Processing Score of 7.2, which is Level 3. Modern margarine avoids trans fats but remains far more processed than butter.
Does margarine still contain trans fats?
Most modern margarines have eliminated partially hydrogenated oils (the trans fat source) following the 2018 FDA ban. They now use interesterified oils or palm oil blends. Check labels; some imported or older formulations may still contain partially hydrogenated oils.
What is interesterification?
Interesterification rearranges the fatty acid molecules on a glycerol backbone using enzymes or chemical catalysts. This changes the oil's melting point from liquid to solid without creating trans fats. It is a laboratory-scale chemical process that replaced hydrogenation in modern margarine production.